Forthcoming Conference

This study investigates the various conceptions held by K‐8th Korean grade students regarding the ‘changes of state’ and the ‘conditions for changes of state’. The study used a sample of five kindergarteners, five secondgrade students, five fourth‐grade students, five sixth‐grade students, and five eighth‐grade students. The 25 students attend schools in a rural district of South Korea. Some activities that involved a change in the state of water, including condensation, solidification, and melting, were chosen from K‐8th grade science textbooks and attempted by the students. Subsequently, we conducted interviews with the students. While most kindergarteners and second‐grade students were able to perceive the phenomena involving changes of state, they were unable to express conceptions related to the changes of state and the conditions under which the state the changes. The upper‐grade students, on the other hand, had some conception of the invisible gas state. Most of these students held conceptions about the boiling water's change of state from liquid to gas, but few of them held conceptions about the changes of state involving condensation. Most students understood heat and temperature as conditions of the changes of state, but only applied the heat concept to situations involving rising temperatures. In situations involving cooling, students applied the temperature concept. The younger students understood the concept of heat without understanding the concept of temperature.     

Desalination characteristics for ceramics excavated from Taean shipwreck,Korea

The ceramic artefacts, excavated from ancient shipwrecks, are generally saturated with soluble salts, mainly NaCl, within the porous structure of ceramics. The salinity contents typically exhibit ionic and osmotic pressures to the ceramic microstructures, thus causing significant damages to the integrity of ceramic artefacts. While the utilisation of aqueous soaking methods is commonly accepted for effective desalination processes of ceramics, the relationships between the structural characteristics of ceramics and the desalination efficiency have not been demonstrated. In this study, we examined the desalination processes of various ceramics excavated from the Taean shipwrecks in South Korea to identify major controlling factors for the desalination processes. Our results indicated that the physical properties of ceramics including the water absorption and the pore size distribution greatly influence on the desalination process time and efficiency. It is also found that the surface condition of ceramic samples such as microstructural cracks on the glaze layer is a crucial component of the desalination characteristics. Nevertheless, the small residue of salts such as NaCl crystals were found in the microstructures of some ceramics after prolonged desalination periods. Therefore, it is important to control the humidity and temperature in the conservation environment for desalinated ceramic artefacts even after desalination.     

Non-positional cell microarray prepared by shape-coded polymeric microboards: A new microarray format for multiplex and high throughput cell-based assays

A non-positional (or suspension) cell microarray was developed using shape-coded SU-8 photoresist microboards for potential application in multiplex and high-throughput cell-based assays. A conventional photolithography process on glass slides produced various shapes of SU-8 micropatterns that had a lateral dimension of 200 μm and a thickness of 40 μm. The resultant micropatterns were detached from the slides by sonication and named "microboards" due to the fact that had a much larger lateral dimension than thickness. The surfaces of the SU-8 microboards were modified with collagen to promote cell adhesion, and it was confirmed that collagen-coated SU-8 microboards supported cell adhesion and proliferation. Seeding of cells into poly(ethylene glycol)(PEG) hydrogel-coated well plates containing collagen-modified microboards resulted in selective cell adhesion onto the microboards due to the non-adhesiveness of PEG hydrogel toward cells, thereby creating non-positional arrays of microboards carrying cells. Finally, two different cell types (fibroblasts and HeLa cells) were separately cultured on different shapes of microboards and subsequently mixed together to create a non-positional cell microarray consisting of multiple cell types where each cell could be easily identified by the shape of the microboard to which they had adhered. Because numerous unique shapes of microboards can be fabricated using this method by simply changing the photomask designs, high throughput and multiplex cell-based assays would be easily achieved with this system in the future.     

Feedback effect of brand extension in cable networks established by parent newspaper brands: applying expectation disconfirmation theory

ABSTRACT

In the present study, we constructed a new research model to understand the feedback effects of brand extension by applying expectation disconfirmation theory to a real-world case of brand extension among South Korean newspapers. We found that the feedback effect was significant in brand extension efforts between the newspaper and broadcast industries. In addition, the relationships between evaluations of the extension brand and the parent brand were mediated by variables defined by expectation disconfirmation theory, including perceived performance and expectation disconfirmation. We also found that expectation disconfirmation can affect evaluations of the parent brand regardless of the perceived fit. Finally, we verified that expectation disconfirmation differs according to the level of perceived fit.     

Growth Mixture Modeling With Nonnormal Distributions: Implications for Data Transformation

This study investigated the extent to which class-specific parameter estimates are biased by the within-class normality assumption in nonnormal growth mixture modeling (GMM). Monte Carlo simulations for nonnormal GMM were conducted to analyze and compare two strategies for obtaining unbiased parameter estimates: relaxing the within-class normality assumption and using data transformation on repeated measures. Based on unconditional GMM with two latent trajectories, data were generated under different sample sizes (300, 800, and 1500), skewness (0.7, 1.2, and 1.6) and kurtosis (2 and 4) of outcomes, numbers of time points (4 and 8), and class proportions (0.5:0.5 and 0.25:0.75). Of the four distributions, it was found that skew-t GMM had the highest accuracy in terms of parameter estimation. In GMM based on data transformations, the adjusted logarithmic method was more effective in obtaining unbiased parameter estimates than the use of van der Waerden quantile normal scores. Even though adjusted logarithmic transformation in nonnormal GMM reduced computation time, skew-t GMM produced much more accurate estimation and was more robust over a range of simulation conditions. This study is significant in that it considers different levels of kurtosis and class proportions, which has not been investigated in depth in previous studies. The present study is also meaningful in that investigated the applicability of data transformation to nonnormal GMM.     

Welfare recipients' involvement with child protective services after welfare reform

OBJECTIVE: This study identifies factors associated with child protective services (CPS) involvement among current and former welfare recipients after welfare reform legislation was passed in the US in 1996. METHOD: Data come from the Women's Employment Study, a longitudinal study of randomly selected welfare recipients living in a Michigan city in 1997 (N=541). In order to identify risk factors for CPS involvement among current and former welfare recipients, multinomial logit analyses with 29 independent variables were employed on a trichotomous dependent variable: no CPS involvement, investigation only, and supervision by CPS after investigation. RESULTS: The relationship between work and involvement with CPS differs by work experience prior to welfare reform. As the percentage of months working after welfare reform increased, the risk of being investigated by CPS declined among those with prior work experience but the risk increased among those without prior work experience. However, work variables were not significant predictors of supervision by CPS after an initial investigation. Further, race, cohabitation, childhood welfare receipt, having a learning disability, having a large number of children, being newly divorced, living in a high problem neighborhood, and being convicted of a crime were associated with one's probability of being either investigated or supervised by CPS. CONCLUSIONS: These findings suggest that employment could have increased the stress levels of current or former welfare recipients without prior work experience to the point where they were prone to minor child rearing mistakes that resulted in a CPS investigation, but were not severe enough to warrant opening the case for supervision. Supports should be provided to welfare mothers who are prone to involvement with CPS; expansions in the childcare subsidy and a reduction or delay in work requirements might also help these families.     

The effects of digital storytelling on student achievement,social presence,and attitude in online collaborative learning environments

This study investigated the effects of digital storytelling on student achievement, social presence, and attitude in online collaborative learning environments. Students in one middle school course were randomly assigned to one of the two treatment groups after they received initial general instruction regarding teamwork skills. The “digital storytelling-based online collaborative learning (DST-OCL)” and the “general online collaborative learning (G-OCL)” groups received subsequent associated skills training. The overall results indicated that after each group took part in the treatment during online collaborative learning activities, the “DST-OCL” groups had significantly higher social presence than the “G-OCL” groups. Specifically, using “DST-OCL” strategies was significantly more effective than using “G-OCL” strategies for improving the “online communication,” “interactivity,” and “privacy” components of students’ social presence in online collaborative learning environments. There was no significant difference between the two groups regarding student achievement and attitude. The findings of this study offer an insight into methods for using digital storytelling as an instructional strategy for improving online collaborative learning effectiveness.     

Effects of self-questioning on EFL students’ engagement in literary reading / Los efectos del autocuestionamiento en la lectura comprometida de textos literarios de estudiantes de inglés como lengua extranjera

This study examines the effects of self-questioning on EFL students’ literary reading engagement. Two interventions were tested: (1) students generating questions while reading short stories, and then exploring their questions in small-groups; and (2) students generating questions while reading, and then reflecting through a free writing activity. Participants were 59 Vietnamese undergraduate students enrolled in an English as a foreign language course. A pre-test post-test control group design with switching replications was used, with a control condition in which the teacher (instead of the students) posed the questions. Students’ reading engagement was measured by a written response to a short story and a questionnaire. Results showed that both self-questioning interventions positively influenced students’ reading engagement compared to the control condition. A maintenance of effects was also observed. We conclude that self-questioning combined with group discussions or free writing promotes students’ reading engagement.     

IMPLEMENTATION OF THE SCIENCE WRITING HEURISTIC (SWH) APPROACH IN 8TH GRADE SCIENCE CLASSROOMS

Current initiatives in science education in Korea have emphasized science literacy as the most important purpose of science education; that is, science education needs to focus on helping each student to become a scientifically literate person who is able to make reasoned decisions. In attempting to address this focus concern about science literacy, the researchers of this study attempted to implement the Science Writing Heuristic (SWH) approach and examined both the SWH and the control groups using the modified Reformed Teaching Observation Protocol (RTOP). Students’ performance on a Summary Writing Test (SWT) was also examined. Participant students of this study were eighth grade students in three middle schools located in the second biggest city in Korea. Each of the three teachers from three schools taught both the SWH and the control classes. The results of this study showed significant differences between the SWH and the control groups on the SWT. There was a difference in the total RTOP scores between the SWH and the control groups. Differences among schools imply that higher level of teachers’ implementation of the SWH approach would appear to result in better student achievement.